tik-tac-toc game main activity code

public class MainActivity extends ActionBarActivity {

// 0 = yellow, 1 = red

    int activePlayer = 0;

    boolean gameIsActive = true;

    // 2 means unplayed

    int[] gameState = {2, 2, 2, 2, 2, 2, 2, 2, 2};

    int[][] winningPositions = {{0, 1, 2}, {3, 4, 5}, {6, 7, 8}, {0, 3, 6}, {1, 4, 7}, {2, 5, 8}, {0, 4, 8}, {2, 4, 6}};

    /**

     * ATTENTION: This was auto-generated to implement the App Indexing API.

     * See https://g.co/AppIndexing/AndroidStudio for more information.

     */

    private GoogleApiClient client;

    public void dropIn(View view) {

        ImageView counter = (ImageView) view;

        int tappedCounter = Integer.parseInt(counter.getTag().toString());

        if (gameState[tappedCounter] == 2 && gameIsActive) {

            gameState[tappedCounter] = activePlayer;

            counter.setTranslationY(-1000f);

            if (activePlayer == 0) {

                counter.setImageResource(R.drawable.yellow);

                activePlayer = 1;

            } else {

                counter.setImageResource(R.drawable.red);

                activePlayer = 0;

            }

            counter.animate().translationYBy(1000f).rotation(360).setDuration(300);

            for (int[] winningPosition : winningPositions) {

                if (gameState[winningPosition[0]] == gameState[winningPosition[1]] &&

                        gameState[winningPosition[1]] == gameState[winningPosition[2]] &&

                        gameState[winningPosition[0]] != 2) {

                    // Someone has won!

                    gameIsActive = false;

                    String winner = "Red";

                    if (gameState[winningPosition[0]] == 0) {

                        winner = "Yellow";

                    }

                    TextView winnerMessage = (TextView) findViewById(R.id.winnerMessage);

                    winnerMessage.setText(winner + " has won!");

                    LinearLayout layout = (LinearLayout) findViewById(R.id.playAgainLayout);

                    layout.setVisibility(View.VISIBLE);

                } else {

                    boolean gameIsOver = true;

                    for (int counterState : gameState) {

                        if (counterState == 2) gameIsOver = false;

                    }

                    if (gameIsOver) {

                        TextView winnerMessage = (TextView) findViewById(R.id.winnerMessage);

                        winnerMessage.setText("It's a draw");

                         LinearLayout layout = (LinearLayout) findViewById(R.id.playAgainLayout);

                        layout.setVisibility(View.VISIBLE);

                    }

                }

            }

        }

    }

    public void playAgain(View view) {

        gameIsActive = true;

        LinearLayout layout = (LinearLayout) findViewById(R.id.playAgainLayout);

        layout.setVisibility(View.INVISIBLE);

        activePlayer = 0;

        for (int i = 0; i < gameState.length; i++) {

            gameState[i] = 2;

        }

        GridLayout gridLayout = (GridLayout) findViewById(R.id.gridLayout);

        for (int i = 0; i < gridLayout.getChildCount(); i++) {

            ((ImageView) gridLayout.getChildAt(i)).setImageResource(0);

        }

    }